DOCSLIB.ORG

Meeting Report of the WHO Evidence Review Group on Mass Drug Administration for Malaria

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Meeting Report of the WHO Evidence Review Group on Mass Drug Administration for Malaria Malaria Policy Advisory Committee Meeting 10–12 April 2019, Geneva, Switzerland Background document for Session 7 Meeting report of the WHO Evidence Review Group on mass drug administration for malaria 11–13 September 2018, Geneva, Switzerland Summary Mass drug administration (MDA), the strategy of administering antimalarials to all age groups of a defined population (except those for whom the drugs are contraindicated) at the same time regardless of infection status, has recently received renewed interest for its potential to accelerate malaria elimination through rapid and sustained reduction of transmission. In 2015, the World Health Organization (WHO) recommended that the use of time-limited MDA in combination with other malaria control measures could be considered in the following scenarios: in areas approaching interruption of Plasmodium falciparum transmission; in the Greater Mekong subregion (GMS) as a component of accelerated malaria elimination efforts; and in epidemics and complex emergencies to reduce morbidity and mortality. Since WHO’s recommendation, new studies have been conducted in areas of low to moderate transmission in Africa and in the GMS, generating additional data on the role of MDA in rapidly reducing transmission. In light of the new data, WHO convened an evidence review meeting to revise and refine the current recommendations on MDA to accelerate malaria elimination, focusing on the evidence emerging from several studies in African countries and the GMS. Modelling studies and results of the update to the Cochrane Systematic Review were also presented and discussed at the meeting. This meeting report provides a summary of the evidence presented, draft conclusions and a proposed update to the WHO recommendations. The report is submitted to the WHO Malaria Policy Advisory Committee (MPAC) for consideration. Conclusions Across all transmission settings: • MDA may rapidly reduce, but does not interrupt, malaria transmission in the short term (1–3 months after the last round) across all transmission intensities when implemented along with vector control and case management. • Short-term reductions in malaria transmission from MDA have only been sustained (4–36 months after the last round) in areas of very low to low transmission (RDT/microscopy parasite prevalence <10%) and in island settings with moderate transmission (up to 15% prevalence). Maintaining reductions in transmission after the last round of MDA requires additional This document was prepared as a pre-read for the meeting of the Malaria Policy Advisory Committee and is not an official document of the World Health Organization. WHO/CDS/GMP/MPAC/2019.04 interventions, including vector control, case management, and intensified surveillance and response. • Two factors strongly associated with the success of MDA in reducing malaria transmission in the short term are high coverage of the population with MDA (a large proportion of the population receiving at least one round of MDA), which may be achieved with more than one consecutive round per year, and focusing a second round on those missed in the first round. • The decision to initiate an MDA campaign to accelerate elimination should be based on the balance between the risks of treating the whole eligible population, very few of whom (in a low transmission setting) may be at risk of malaria, and the potential benefits from cases averted. The decision to use MDA to rapidly reduce transmission should also consider whether MDA is cost-effective compared to other interventions. In moderate to high transmission settings (parasite prevalence ≥10%): • There is evidence from both a systematic review and the most recent research studies that MDA reduces the transmission of P. falciparum in moderate transmission settings (parasite prevalence 10–35%) in the first three months after the last round of MDA is completed, but the evidence is inconclusive from areas of high transmission (parasite prevalence ≥35%). Evidence suggests that the short-term impact of MDA programmes in moderate transmission settings has likely been enhanced by the presence of additional interventions, including vector control and case management. • The evidence reviewed suggested that the reduction in malaria transmission from MDA could be sustained for up to three years in island settings in areas of moderate P. falciparum transmission up to a parasite prevalence of 15% when additional interventions are in place, including vector control, case management and intensified surveillance. In very low to low transmission settings (parasite prevalence <10%): • There is evidence from recent research studies that MDA reduces transmission of P. falciparum in the first three months after completion of the last round of MDA in low transmission settings (parasite prevalence 1–10%). However, there is no evidence that MDA, even in conjunction with vector control and good case management, can interrupt transmission. No evidence was available for review from very low transmission settings (parasite prevalence <1%). • The impact of MDA on P. falciparum was sustained in many low transmission settings for more than 30 months when additional interventions were deployed, including vector control, community-based case management and intensified surveillance. Impact on P. vivax: • Two studies of MDA in the GMS using an artemisinin-based combination therapy (ACT) plus a single low dose of primaquine (PQ) reported differing results for P. vivax, with one study demonstrating only a short-term reduction in P. vivax transmission and the other study finding no effect. Meeting report of the WHO Evidence Review Group on mass drug administration for malaria | 2 • Historical and recent evidence shows a significant short-term reduction in P. vivax transmission, with lower incidence maintained until the following transmission season and up to six months in temperate areas, following the deployment of PQ mass prophylactic treatment for 14 days in combination with other malaria control interventions. Impact on antimalarial resistance: • Early results from modelling studies indicate that the risk of MDA in selecting for resistant strains rises with an increasing rate of importation of resistant strains into the MDA area. Conversely, the risk may decrease with increased access to antimalarial medicines that were not used for the MDA regimen in the immediate post-MDA period. Proposed update to current recommendations on MDA Based on the above conclusions, the ERG proposes that the existing recommendations on MDA be updated and replaced by the following draft recommendations, which are submitted for consideration to the WHO MPAC. 1. Use of MDA to accelerate progress towards elimination (i.e., significant reductions in malaria transmission sustained over time) of P. falciparum malaria can be considered in areas of very low to low transmission (parasite prevalence <10%) where there is good access to effective treatment and effective implementation of vector control and surveillance, and limited risk of re-introduction of infection. Additionally, MDA can be considered in small islands (<500 000 population) with moderate transmission (P. falciparum parasite prevalence 10–15%) where there is limited risk of re-introduction of parasites, effective treatment, and effective implementation of vector control and surveillance. 2. In settings with moderate to high transmission, MDA may produce a short-term reduction in malaria burden, but so far there is no evidence that MDA, with or without additional interventions, will accelerate progress towards elimination. More evidence should be gathered to determine whether repeated rounds of MDA over multiple years in conjunction with other interventions in these settings could sustain reduced transmission and accelerate progress towards elimination. 3. Mass primaquine prophylactic treatment, requiring pre-seasonal MDA with daily administration of primaquine for two weeks, can be considered as a component of P. vivax elimination strategies in temperate regions, taking into consideration G6PD deficiency. 4. Given the threat of P. falciparum multidrug resistance and the WHO call for malaria elimination in the Greater Mekong subregion (GMS), MDA should be considered as a component of accelerated malaria elimination efforts in the GMS where there is good access to effective treatment and effective implementation of vector control and surveillance, and limited risk of re-introduction of infection. However, because of prevalent multidrug resistance in the region, the options are limited for effective antimalarials that can be used in MDA. 5. Use of time-limited MDA to rapidly reduce malaria morbidity and mortality may be considered for epidemic control as part of the initial response, along with the urgent introduction of other interventions.1 Meeting report of the WHO Evidence Review Group on mass drug administration for malaria | 3 6. Use of time-limited MDA to reduce malaria morbidity and mortality may be considered in complex emergencies, during exceptional circumstances when the health system is overwhelmed and unable to serve the affected communities.1 7. Medicines used for MDA must be of proven efficacy in the implementation area and preferably have a long half-life. WHO recommends that a medicine different from that used for first-line treatment be used for MDA to reduce the risk of development of resistance. Programmes should include drug safety monitoring during MDA campaigns. Drug efficacy should be monitored after the campaign to
Load more

Recommended publications
  • WHO Technical Consultation to Review the Role of Drugs in Malaria Prevention for People Living in Endemic Settings
    Malaria Policy Advisory Committee Meeting 13—14 May 2020, Geneva, Switzerland Background document for Session 5 WHO technical consultation to review the role of drugs in malaria prevention for people living in endemic settings Meeting report, 16–17 October 2019, Geneva, Switzerland Summary On 16–17 October 2019, the World Health Organization (WHO) convened a Technical Consultation to review the use of medicines for malaria prevention in endemic countries and to identify opportunities to increase their impact through review of the flexibility of the recommendations for their deployment. Experts reviewed the policies and use of chemoprevention as currently endorsed by WHO, including intermittent preventive treatment in pregnancy (IPTp), intermittent preventive treatment in infants (IPTi), seasonal malaria chemoprevention (SMC) and mass drug administration (MDA) for the reduction of disease burden in emergency situations. By reviewing these strategies side-by-side for the first time, the meeting was able to consider opportunities for optimization. Additional potential applications of chemoprevention were also reviewed, and key considerations identified to develop a broader role for malaria chemoprevention in malaria-endemic populations. Key conclusions of the meeting included: • There is a need for general guidance on the broader use of chemoprevention. Chemoprevention is an important approach in the package of strategies that countries may use to decrease their malaria burden and/or move towards malaria elimination. Development of broader, more flexible guidance that builds on existing chemoprevention recommendations in specific populations is expected to support the greater, more rational use of chemoprevention and enhance its impact. • Chemoprevention strategies may be tailored to country-specific needs. Guidance should be flexible enough to enable adaptation of strategies according to the needs of different countries and settings.
    [Show full text]
  • The Safety and Effectiveness of Single Dose Primaquine As a P
    Malaria Policy Advisory Committee Meeting 11-13 September 2012, WHO HQ Session 5 WHO Evidence Review Group: The Safety and Effectiveness of Single Dose Primaquine as a P. falciparum gametocytocide Pullman Hotel, Bangkok, Thailand, 13-15 August 2012 Meeting Report Background Deployed since the early 1950s primaquine is the most Glossary: widely used 8-aminoquinoline antimalarial drug. It has been used extensively in the radical treatment of P. vivax G6PD: Glucose-6-phosphate dehydrogenase and P. ovale malaria, and as a single dose G6PDd: G6PD deficient gametocytocide in falciparum malaria. The main limitation to its use has been haemolytic toxicity. The 8- AHA: Acute haemolytic anaemia aminoquinoline antimalarials produce dose dependent acute haemolytic anaemia (AHA) in individuals who have ACT: Artemisinin combination treatment G6PD deficiency, an inherited X-linked abnormality. The MDA: Mass drug administration prevalence of the underlying allelic genes for G6PD deficiency varies typically between 5 and 32.5 % in POC: Point of care malaria endemic areas of Asia and Africa. Use of primaquine as a gametocytocide has great potential to reduce the transmission of falciparum malaria in low transmission settings, and in particular to help contain the spread of artemisinin resistant falciparum malaria in SouthEast Asia. The World Health Organisation currently recommends addition of primaquine 0.75 mg base/kg (adult dose 45 mg) to treatment regimens for P. falciparum malaria in areas of low transmission, particularly in areas where artemisinin resistant falciparum malaria is a threat, “when the risk for G6PD deficiency is considered low or testing for deficiency is available”. Unfortunately there is often uncertainty about the prevalence and severity of G6PD deficiency, and testing for it is usually not available in these areas.
    [Show full text]
  • Understanding Adherence to Reactive Treatment of Asymptomatic Malaria
    www.nature.com/scientificreports OPEN Understanding adherence to reactive treatment of asymptomatic malaria infections in The Gambia Fatou Jaiteh1,2,3*, Joseph Okebe1,4, Yoriko Masunaga2,3, Umberto D’Alessandro1, Jane Achan1, Charlotte Gryseels2, Daniel de Vries3, Joan Muela Ribera5 & Koen Peeters Grietens2,5,6 The impact of diferent types of reactive case detection and/or treatment strategies for malaria elimination depends on high coverage and participants’ adherence. However, strategies to optimise adherence are limited, particularly for people with asymptomatic or no infections. As part of a cluster-randomized trial to evaluate the efect of reactive treatment in The Gambia, all residents in the compound of a diagnosed clinical malaria patient received dihydro-artemisinin–piperaquine (DP). Using a mixed method approach, we assessed which factors contribute to adherence among the contacts of malaria cases that showed no symptoms. Adherence was defned as the proportion of compound members that (1) returned all medicine bags empty and (2) self-reported (3-day) treatment completion. Among the 273 individuals from 14 compounds who received DP, 227 (83.1%) were available for and willing to participate in the survey; 85.3% (233/273) returned empty medicine bags and 91.6% (208/227) self-reported treatment completion. Although clinical malaria was not considered a major health problem, reported adherence was high. The drivers of adherence were the strong sense of responsibility towards protecting the individual, compound and the village. Adherence can be optimised through a transdisciplinary implementation research process of engaging communities to bridge the gap between research goals and social realities. Malaria infected but asymptomatic carriers (i.e.
    [Show full text]
  • Review of Mass Drug Administration and Primaquine
    Contents Acknowledgements ...................................................................................................................................... 2 Acronyms ...................................................................................................................................................... 3 Introduction .................................................................................................................................................. 4 Methods ....................................................................................................................................................... 4 Findings ......................................................................................................................................................... 6 Study objectives and design ............................................................................................................ 9 Contextual parameters - endemicity, seasonality, target population .......................................... 10 Outcome measures ....................................................................................................................... 13 Drug regimens ............................................................................................................................... 13 Co-Interventions ............................................................................................................................ 15 Delivery methods and community engagement ..........................................................................
    [Show full text]
  • A Guide for Independent Monitoring of Mass Drug Administration for Neglected Tropical Disease Control
    A Guide for Independent Monitoring of Mass Drug Administration for Neglected Tropical Disease Control A case study from Sierra Leone Helen Keller International Table of Contents 1.0 - Introduction ........................................................................................................................... 4 2.0 - Overview of Independent Monitoring .................................................................................... 5 3.0 - Independent Monitors ........................................................................................................... 6 3.1 - Training of the Independent Monitors ............................................................................... 6 4.0 - Sampling ............................................................................................................................... 8 4.1 - Sampling steps .................................................................................................................. 8 4.2 - Sampling of sites for in-process monitoring ...................................................................... 9 4.3 - Sampling of sites for end-process monitoring ................................................................. 10 5.0 - Interviews ............................................................................................................................ 11 5.1 - Household interviews ...................................................................................................... 11 5.2 - Community interviews ....................................................................................................
    [Show full text]
  • Mass Drug Administration, Mass Screening and Treatment and Focal Screening and Treatment for Malaria
    Malaria Policy Advisory Committee Meeting 16–18 September 2015, Geneva, Switzerland Background document for Session 1 Mass drug administration, mass screening and treatment and focal screening and treatment for malaria WHO Evidence Review Group meeting report WHO Headquarters, Geneva 20–22 April 2015 Summary Mass drug administration (MDA) has received renewed interest over the past decade in the context of malaria elimination, as part of multidrug resistance containment and (more recently) in emergency situations such as the West African Ebola outbreak. To develop WHO recommendations, a group of experts met in April 2015 to review recent evidence on the use of MDA, mass screening and treatment (MSAT) and focal screening and treatment (FSAT) in specific epidemiological settings. The following recommendations were proposed by the WHO evidence review group, for consideration by the WHO Malaria Policy Advisory Committee. Proposed recommendations 1. Use of MDA to interrupt transmission of falciparum malaria can be considered in endemic island communities and in low-endemic non-island settings approaching elimination, where there is minimal risk of re-introduction of infection, good access to treatment, and implementation of vector control and surveillance. 2. In view of the growing threat of multidrug resistance and the need to use extreme measures, MDA can be considered as a component of malaria elimination efforts in the Greater Mekong subregion, in areas with good access to treatment, vector control and good surveillance. 3. Use of MDA to rapidly reduce malaria morbidity and mortality can be consid¬ered for epidemic control as part of the immediate response, while other interventions are put in place.
    [Show full text]
  • The Challenge of Schistosomiasis Frank O Richards Jr,A Abel Eigege,B Emmanuel S Miri,B MY Jinadu,C & Donald R Hopkins A
    Integration of mass drug administration programmes in Nigeria: the challenge of schistosomiasis Frank O Richards Jr,a Abel Eigege,b Emmanuel S Miri,b MY Jinadu,c & Donald R Hopkins a Problem Annual mass drug administration (MDA) with safe oral anthelminthic drugs (praziquantel, ivermectin and albendazole) is the strategy for control of onchocerciasis, lymphatic filariasis (LF) and schistosomiasis. District health officers seek to integrate treatment activities in areas of overlapping disease endemicity, but they are faced with having to merge different programmatic guidelines. Approach We proceeded through the three stages of integrated MDA implementation: mapping the distribution of the three diseases at district level; tailoring district training and logistics based on the results of the mapping exercises; and implementing community- based annual health education and mass treatment where appropriate. During the process we identified the “know–do” gaps in the MDA guidelines for each disease that prevented successful integration of these programmes. Local setting An integrated programme launched in 1999 in Plateau and Nasarawa States in central Nigeria, where all three diseases were known to occur. Relevant changes Current guidelines allowed onchocerciasis and LF activities to be integrated, resulting in rapid mapping throughout the two states, and states-wide provision of over 9.3 million combined ivermectin–albendazole treatments for the two diseases between 2000 and 2004. In contrast, schistosomiasis activities could not be effectively integrated because of the more restrictive guidelines, resulting in less than half of the two states being mapped, and delivery of only 701 419 praziquantel treatments for schistosomiasis since 1999. Lessons learned Integration of schistosomiasis into other MDA programmes would be helped by amended guidelines leading to simpler mapping, more liberal use of praziquantel and the ability to administer praziquantel simultaneously with ivermectin and albendazole.
    [Show full text]
  • Envisage Repurposing Ivermectin for SARS-COV-2
    Am. J. Trop. Med. Hyg., 103(1), 2020, pp. 10–11 doi:10.4269/ajtmh.20-0295 Copyright © 2020 by The American Society of Tropical Medicine and Hygiene Stories from the Field Mass Drug Administration and Worms Experience in Africa: Envisage Repurposing Ivermectin for SARS-COV-2 Claire Njeri Wamae1,2* 1School of Pharmacy and Health Sciences, United States International University-Africa, Nairobi, Kenya; 2Kenya Medical Research Institute, Nairobi, Kenya I have spent over 40 years studying parasitic worms and the (Zithromax), among others. By 2018, up to 1.752 billion drugs we use to treat them. With this background, I suggest treatments were distributed to affected populations through- that large-scale annual mass drug administration for pre- out endemic areas in the world. As of 2015, 99% of persons ventive chemotherapy of neglected tropical diseases may be infected by Onchocerca volvulus globally were living in 31 contributing to keeping COVID-19 cases in check and below African countries (http://www.who.int/gho); thus, Africa projections in Africa. received the bulk of ivermectin donations. My fascination with worms started in 1979, while un- A casual look at the O. volvulus (http://www.who.int/gho) dertaking a food science major in college. I was dismayed to and COVID-19 (http://africacdc.org) maps lacks the typical learn of tiny blackflies that breed in fast-flowing rivers in Africa neglected tropical disease overlaps. In equatorial Africa, we and transmit river blindness! What horrified me most about the commonly find high prevalence and overlaps of the afore- strange disease was the textbook picture depicting a naked mentioned five diseases in same geographical areas (pop- blind African adult man, led on a cane by a little boy (naked ulations).
    [Show full text]
  • G6PD Deficiency in Latin America: Systematic Review on Prevalence and Variants
    Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 109(5): 553-568, August 2014 553 G6PD deficiency in Latin America: systematic review on prevalence and variants Wuelton M Monteiro1,2/+, Fernando FA Val1,2, André M Siqueira1,2, Gabriel P Franca1, Vanderson S Sampaio1,2, Gisely C Melo1,2, Anne CG Almeida1,2, Marcelo AM Brito1,2, Henry M Peixoto3, Douglas Fuller4, Quique Bassat5, Gustavo AS Romero3,6, Maria Regina F Oliveira3,6, Marcus Vinícius G Lacerda1,2 1Gerência de Malária, Fundação de Medicina Tropical Dr Heitor Vieira Dourado, Manaus, AM, Brasil 2Escola Superior de Ciências da Saúde, Universidade do Estado do Amazonas, Manaus, AM, Brasil 3Faculdade de Medicina, Universidade de Brasília, Brasília, DF, Brasil 4Department of Geography and Regional Studies, University of Miami, Coral Gables, FL, USA 5Barcelona Centre for International Health Research, Hospital Clinic, University of Barcelona, Barcelona, Spain 6Instituto Nacional de Ciência e Tecnologia para Avaliação de Tecnologias em Saúde, Porto Alegre, RS, Brasil Plasmodium vivax radical cure requires the use of primaquine (PQ), a drug that induces haemolysis in glucose- 6-phosphate dehydrogenase deficient (G6PDd) individuals, which further hampers malaria control efforts. The aim of this work was to study the G6PDd prevalence and variants in Latin America (LA) and the Caribbean region. A sys- tematic search of the published literature was undertaken in August 2013. Bibliographies of manuscripts were also searched and additional references were identified. Low prevalence rates of G6PDd were documented in Argentina, Bolivia, Mexico, Peru and Uruguay, but studies from Curaçao, Ecuador, Jamaica, Saint Lucia, Suriname and Trini- dad, as well as some surveys carried out in areas of Brazil, Colombia and Cuba, have shown a high prevalence (> 10%) of G6PDd.
    [Show full text]
  • Lymphatic Filariasis: Elimination in the Americas
    Lymphatic Filariasis: Elimination in the Americas Center for Global Health Division of Parasitic Diseases and Malaria The Burden of Lymphatic Filariasis (LF) To date, close to 700 million people in some of the poorest areas globally have received treatment to prevent one of the world’s most incapacitating diseases, lymphatic filariasis. ymphatic filariasis (LF) is a disabling parasitic disease caused Lby microscopic worms that are spread from person-to-person by the bite of an infected mosquito. The adult worms live in the human lymphatic system and can cause lymphedema (swelling) affecting the legs, arms, or breasts. They can also cause hydrocele (severe fluid accumulation) affecting the genitalia of men. Chronic manifestations of lymphatic filariasis, which usually take place years after initial infection, can cause pain, severe and irreversible disfigurement, and stigmatization. Lymphatic filariasis is one of the world’s neglected tropical diseases (NTDs), a group of infectious diseases affecting more than 1 billion people that is responsible for tremendous suffering and economic loss. LF is recognized as one of the most disabling and economically costly NTDs, as infection with the disease can lead to lower productivity and inability to work. Over 120 million persons are infected with LF, a disease that can be eliminated In 2000, the World Health Organization launched The Global Programme to Eliminate Lymphatic Filariasis, with a target elimination date of 2020. This initiative is driven by a two-fold strategy to interrupt the spread of infection and reduce the suffering of persons already infected. These efforts to interrupt transmission and improve disease management ensure that future generations will not suffer the same disability.
    [Show full text]
  • Evaluation of Mass Drug Administration Impact on Transmission of Lymphatic Filariasis in 13 Sanitary Districts in Burkina Faso
    Journal of Cosmetics, Dermatological Sciences and Applications, 2018, 8, 185-194 http://www.scirp.org/journal/jcdsa ISSN Online: 2161-4512 ISSN Print: 2161-4105 Evaluation of Mass Drug Administration Impact on Transmission of Lymphatic Filariasis in 13 Sanitary Districts in Burkina Faso Nomtondo Amina Ouedraogo1*, Sidnoma Muriel Ouedraogo1, Gilbert Patrice Tapsoba1, W. Roland Bougma2, Mamadou Serme3, Apollinaire Kima3, Nadia Kaboret4, Ibrahim Sangare3, Clarisse Bougouma3, François Drabo3 1Research and Training Unit in Health Sciences, University Ouaga I Pr Joseph Ki-Zerbo, Ouagadougou, Burkina Faso 2Neglected Tropical Diseases National Program, Lymphatic Filariasis Unit, Ouagadougou, Burkina Faso 3Neglected Tropical Diseases National Program (NTD NP), Ouagadougou, Burkina Faso 4University Hospital of Tengandogo, Ouagadougou, Burkina Faso How to cite this paper: Ouedraogo, N.A., Abstract Ouedraogo, S.M., Tapsoba, G.P., Bougma, W.R., Serme, M., Kima, A., Kaboret, N., Introduction: Lymphatic filariasis (LF) is one of the neglected tropical dis- Sangare, I., Bougouma, C. and Drabo, F. eases targeted for elimination as a public health issue in the world by 2020. To (2018) Evaluation of Mass Drug Adminis- achieve this goal, one of the strategies is interruption of transmission using tration Impact on Transmission of Lym- phatic Filariasis in 13 Sanitary Districts in chemotherapy (mass drug administration). Burkina Faso in west Africa, an Burkina Faso. Journal of Cosmetics, Der- endemic country, has endorsed this resolution. In 2000, all Sanitary Districts matological Sciences and Applications, 8, (SD) in the country were endemic, and then a national elimination program 185-194. has made it possible to stop mass treatment in 45 out of 70 SD over 12 years.
    [Show full text]
  • Impact of Five Annual Rounds of Mass Drug Administration with Ivermectin on Onchocerciasis in Sierra Leone Joseph B
    Koroma et al. Infectious Diseases of Poverty (2018) 7:30 https://doi.org/10.1186/s40249-018-0410-y RESEARCH ARTICLE Open Access Impact of five annual rounds of mass drug administration with ivermectin on onchocerciasis in Sierra Leone Joseph B. Koroma1, Santigie Sesay2, Abdul Conteh2, Benjamin Koudou3, Jusufu Paye4, Mohamed Bah4, Mustapha Sonnie4, Mary H. Hodges4, Yaobi Zhang5* and Moses J. Bockarie6 Abstract Background: Onchocerciasis is endemic in 12 of the 14 health districts of Sierra Leone. Good treatment coverage of community-directed treatment with ivermectin was achieved between 2005 and 2009 after the 11-year civil conflict. Sentinel site surveys were conducted in 2010 to evaluate the impact of five annual rounds of ivermectin distribution. Methods: In total, 39 sentinel villages from hyper- and meso-endemic areas across the 12 endemic districts were surveyed using skin snips in 2010. Results were analyzed and compared with the baseline data from the same 39 villages. Results: The average microfilaridermia (MF) prevalence across 39 sentinel villages was 53.10% at baseline. The MF prevalence was higher in older age groups, with the lowest in the age group of 1–9 years (11.00%) and the highest in the age group of 40–49 years (82.31%). Overall mean MF density among the positives was 28.87 microfilariae (mf)/snip, increasing with age with the lowest in the age group of 1–9 years and the highest in the age group of 40–49 years. Males had higher MF prevalence and density than females. In 2010 after five rounds of mass drug administration, the overall MF prevalence decreased by 60.26% from 53.10% to 21.10%; the overall mean MF density among the positives decreased by 71.29% from 28.87 mf/snip to 8.29 mf/snip; and the overall mean MF density among all persons examined decreased by 88.58% from 15.33 mf/snip to 1.75 mf/snip.
    [Show full text]